Прошедшая форма инфинитива:   have+ V3

should –следует ( модальный глагол)

would –бы ( модальный глагол)

seem –кажется

Сравни: Тебе следует говорить более бегло –You should speak more fluently (настоящее).

Тебе следовало говорить более бегло –You should  have spoken more fluently (прошедшее.)  Это предложение так же можно перевести: «Зря ты не говорил бегло»

Твое выступление было бы лучше ( в будущем) - Your speech would be better.

Твое выступление было бы лучше ( в прошлом) - Your speech would have been better.

Кажется, он все знает ( настоящее) –He seems to know everything.

Кажется, он ошибся ( прошедшее)-  He seems to have made a mistake

Кажется он не все сказал ( прошедшее)  - He doesn`t seem to have said everything

Expressing opinions:

1.       He should have spoken more…slowly/ fluently/

He should have been more confident.

Ему следовало стараться смотреть в глаза.

Ему не следовало смеяться, когда он выступал.

2.       He doesn`t seem to have mentioned…

He seems to have forgotten…

He seems to have been mistaken

3.       I`d (would) like to make some comments.

I`d like to add… I`d like to comment on his ( way of speaking, speech, fluency).

4.       I have one more thing to add.  One more thing to comment on.  It is the choice of ( vocabulary, grammar, facts, useful phrases…)

+     He used a good range of vocabulary (structures, facts,)

-          The range of vocabulary was (rather) limited

Well, in my opinion, he spoke well/ he spoke rather well/ his speech was OK/

Personally, I think, …

To be honest,…= Frankly, I..

What I liked most about his speech is…that he sounded confident

What I liked most about his speech is… his fluency