Some common phenomena________(be) not completely understood by human beings.

What is the relationship between tense and time? How many tenses do English verbs have and what are they?

Combining the following three sentences by using a cohesive device:

Tom’s work at school is above the average. Harry’s work is below the average, Tim’s work is about up to the average.

What principle of concord do we usually apply to agreement between the verb and its subject in the form of a clause? Give examples to illustrate your point of view.

Rewriting the second sentence by using a cohesive device:

A: How do you know that he’s retiring soon?

B: He told me that he’s retiring soon.

Rewriting the sentence into an existential one:

A boy named George Smith sat in the same class as me.

Using a disjunct:

It is possible that the accident happened when I was in the garden.

Using discontinuity:

The assumption that the economy will continue to improve is made.

Using a conjunct:

Officially, the general manager is in charge. His secretary does all the work.

Combining the two sentences by using a relative clause:

She is telling a story of Lei Feng. Every one of us is proud of him.

Combining the two sentences by using the non-finite verb form:

She was driving without a license. She was arrested and jailed by the sheriff.