Recently ultrasound is important in the NDT field.

Use present perfect tense to describe recent events that are strongly connected to the present time, e.g.

Recently ultrasound has become important in the NDT field.

Another problem is tense consistency.

The table is not horizontal, so an angle was produced between the horizontal line and steel beam. This is different to the real value of Young’s modulus.

Be consistent with your use of tense. If you are reporting past actions, you should use all past tense verbs, e.g.

The table was not horizontal, so an angle was produced between the horizontal line and steel beam. This was different to the real value of Young’s modulus.

 

We could approximate the switching action by using a signal generator and a diode.

When the focus of the sentence is on what is happening or can happen, you should use the passive voice, e.g.

The switching action can be approximated by using a signal generator and a diode.

The passive voice is particularly useful when describing the procedure of your laboratory experiment.

This problem is due to the roughness of the backing material surface or to the imperfection of sample two.

When explaining the possible reasons for errors in your experiments, or for why the results differ from the theoretical models on which they are based, you need to use modal verbs such as may, might, could, can, will, must, have to and should to indicate certainty or degree of probability, e.g.

This could be due to the roughness of the backing material surface, or might be a result of the imperfection in sample two.

Another common error is failing to indicate when an action is essential, e.g.

Because the switching is so rapid, so we can use the CRO to study the change of current.

You should ensure that you use must or have to when it is essential to perform a certain action. The above sentence should look like this:

Because the switching is so rapid, we must use the CRO to study the change of current.

 

This result was not accuracy than our experiment because it was affected by factors b and c.

There are several ways you can compare two things.

For adjectives of one or two syllables, we usually add ~er to the end of the adjective, and than + the object:

A is clearer than B

For words of three or more syllables we use more before the adjective:

B is more accurate than A

For negative expressions:

B is not as clear as A
A is not as accurate as B

 

In this experiment, a static method was used which involves measuring the deflection of a beam when a load was applied.

We use relative clauses often in scientific writing because they can define things quickly. The clause comes immediately after the noun, and if it is a non-defining clause (the most common in scientific writing), it is generally punctuated by commas both before and after the clause, e.g.

In this experiment a static method, which involves measuring the deflection of a beam when a load is applied, was used.

 

If this grounding wire could be replaced by some other technique, the results can be improved.

We use conditionals, or ‘if’ clauses, when we are hypothesising or speculating about events. In scientific English the two most common forms are the following:

1. For likely results in the hypothetical situation, we use the first conditional.

If this grounding wire is replaced, the results will be improved.

If this grounding wire was/were replaced, the results would be improved.

There were some problems with the deflection results. When deflections were measured with ruler or travelling microscope, results showed errors.

There are several errors with articles in the above example. In English we have indefinite articles and definite articles, which are frequently used before nouns.

The sentence should read:

There were some problems with the deflection results. When the deflections were measured with a ruler or a travelling microscope, the results showed errors.

The indefinite article

We use "a" (or "an" if the following noun begins with a vowel) to introduce a general type of object, e.g. a microscope. In scientific writing you will use this most frequently when you mention an object or idea for the first time e.g. "a microscope was used to examine the changes."

The definite article

We use "the" to refer to specific objects or ideas. In scientific writing you will use this to refer to an object or idea that you have already introduced e.g. "the microscope was used only to look for organic changes"


The rules for the use of articles are quite complex, and this is a particularly difficult area for people using English as a second language. If you do make this kind of mistake, you should refer to a good grammar book for more detailed information.

This shows agreement between the experimental and theoretical results. However, some results are disagreeable with the theoretical prediction.

Here the problem is with the student’s choice of the word "agreeable", which is not used in the way s/he thinks. A better choice would be "consistency" in this example.

This shows consistency between the experimental results and the theory. However, some results are inconsistent with the theoretical prediction.

There are no rules you can follow about correct word choice. However, if you are not sure that the word means what you want it to, you must check a good quality dictionary for examples of usage.

The time base and voltage must be set as high as possible when determining the t of the waveform. It is because this can reduce error.

Using "It is because…" at the beginning of a sentence to introduce a reason is a very common error in Hong Kong. For the most part this should simply be replaced by a clause beginning with because + the reason or explanation. A new sentence is not necessary, e.g.

The time base and voltage must be set as high as possible when determining the t of the waveform because this can reduce error.

Alternatively "as" can be used.

The time base and voltage must be set as high as possible when determining the t of the waveform, as this can reduce error.

Another way to explain a reason for something is to put the reason in the first clause and to begin with the infinitive, e.g.

To reduce error, the time base and voltage must be set as high as possible when determining the t of the waveform.

 

When S is closed, the neon lamp will not glow because the voltage is below 50 V. When S is suddenly opened, the lamp will glow for a short time. The voltage of the lamp is greater than 50V.

The sentences in this short paragraph are not linked together clearly, so it’s difficult for the reader to understand the relationship between the events that are being described. To make the sentences and paragraph more cohesive, the writer needs to make clearer connections between the sentences, e.g.

When S is closed, the neon lamp will not glow because the voltage is below 50V. However, when S is suddenly opened, the voltage is greater than 50V, so the lamp will glow for a short time.