H. We can use clauses with that:
a. after verbs of thinking: think, believe, expect, decide, hope, know, understand, suppose, guess, imagine, feel, remember, forget (e.g. I hope that you will enjoy your holiday. She didn’t really think that it would happen. I knew that I had seen her somewhere before.)
b. after verbs of saying: say, admit, argue, reply, agree, claim, deny, mention, answer, complain, explain, promise, suggest (e.g. They admitted that they had made a mistake. She argued that they should invest more in the business. The children complained that they had nothing to do.)
c. Tell and some other verbs of saying must always have a direct object: tell/ convince/ persuade/ inform/ remind (e.g. We tried to tell them that they should stop what they were doing.)
d. as postmodifiers after nouns to do with thinking or saying: advice, belief, claim, feeling, argument, hope, promise, report, guess, opinion, idea (e.g. He made a promise that he would do all he could to help.)
e. after some nouns to say more about the noun: fact, advantage, effect, possibility, chance, danger, evidence, problem, difficulty (e.g. She pointed out the danger that they might be left behind.)
f. We often use a that clause to define one of these nouns after the verb be: danger, problem, chance, possibility, fact (e.g. The danger is that we will be left behind.)
g. after some adjectives which describe feelings to give a reason for our feelings: pleased, sorry, happy, unhappy, sad, excited, glad, disappointed, afraid (e.g. I am sorry that you can’t come.)
H1. No ‘that: We can always use a clause without the word that. (e.g. They admitted they had made a mistake. The police informed everybody the danger was over. I am sorry you can’t come. There was chance we would succeed.)