At school, in English lessons in the middle of the last century, we were taught something called parsing which involved analysing a sentence in terms of its grammar, identifying the parts of speech, and understanding its syntax. I loved parsing and I think this way of looking at language can be helpful in learning foreign languages and in writing in general.

One of the main rules of grammar is that the subject of a sentence must always agree with the verb. In other words, they both must be singular or they both must be plural. You can’t have a singular subject with a plural verb or vice versa.

It would be wrong to say:

• The use of cell phones and laptops are prohibited.

Although cell phones and laptops are plural, the real subject of the sentence is The use which is singular, so the verb should be singular too:

• The use of cell phones and laptops is prohibited.

It would also be wrong to say:

• Your patience and forbearance is very much appreciated.

Although patience and forbearance are both singular, together they form the plural subject of the sentence, so the verb should also be plural:

Your patience and forbearance are very much appreciated.

Sometimes a writer can get distracted by what comes after the verb in a sentence:

• The most common reason for dogs barking are boredom and loneliness.

Although boredom and loneliness joined together by and form a plural, they are not the subject of the sentence which is The most common reason which is singular. The best way of dealing with this would be to make the subject plural:

• The most common reasons for dogs barking are boredom and loneliness.

Similarly it would be wrong to say:

• The cause of this prevalent disease are bad diet and lack of exercise.

Again, bad diet and lack of exercise form a plural, but they are not the subject of the sentence which is The cause of this prevalent disease which is singular. A good way of correcting this would be to make the verb singular and change the format of bad diet and lack of exercise:

• The cause of this prevalent disease is bad diet coupled with lack of exercise.