Verbs commonly followed by that include reporting verbs (say, tell, admit, etc.) and mental process verbs (believe, think, know, hope, etc.). Some verbs connected with reporting can be followed by a that-clause acting as the direct object:

accept decide

insist repeat

admit discover

know reply

agree doubt

mean say

announce expect

mention see

assume explain

notice show

believe feel

pretend state

check find (out)

promise suggest

claim forget

prove suppose

comment guess

realise think

complain

hear reckon

understand confirm

hope remark

consider imagine

remember

.

They said that four million workers stayed at home to protest against the tax.

The survey indicated that 28 per cent would prefer to buy a house through a building society than through a bank.

He knew that something bad had happened.

Do you think that they forgot to pay or that they stole it?

We use be + adjective + that-clause to express opinions and feelings. Some adjectives commonly used in this way are sure, certain, right, important, afraid, pleased, sorry, surprised, worried. We can omit that with no change in meaning. A list of common adjectives: 

afraid anxious ashamed

disappointed frightened
glad happy
pleased proud

sad surprised
unhappy
inclined
liable likely
prepared
ready unlikely
unwilling willing

awful bad
essential  extraordinary
funny good
important interesting
obvious sad true

It’s important (that) we look at the problem in more detail.

I’m sure (that) you’ll know a lot of people there.

They were afraid(that) we were going to be late.

.

We use a noun + that-clause to express opinions and feelings, often about certainty and possibility. We also use that with reporting nouns. Some nouns commonly used in this way are belief, fact, hope, idea, possibility, suggestion, statement, claim, comment, argument:

He is also having intensive treatment in the hope that he will be able to train on Friday.

Dutch police are investigating the possibility that a bomb was planted on the jet.

.

an accident

an advantage

a cause [of]

a concern

a coincidence

a consequence

a disappointment

an effect

a factor / a fact

the fault [of]

a failure

a measure [of]

a miracle

a pity

a problem

a reason

no reason [for]

a result [of]

a shame

a source [of]

a success

a triumph

.

THAT + CLAUSE…………PREDICATE + COMPLEMENT

That we need more people in math and science is clear to everyone.

That we are not prepared for the future concerns us.

That there are too few new scientists is well-known.

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