Czy dobrze rozpoznałem ?

Witam
Prosze o sprawdzenie kilku zdań czy dobrze rozpoznałem zdania pod względem czasów.

It was started in 1968 by the US government, but at first it was used mainly by scientists. Past Simple

In fact, the Internet has been successfully used by people to find lifelong partners. Past Perfect

Since 1990, when the World Wide Web was created, it has changed
the world, and its uses are growing every day. Present Perfect

Students can find some educational aids to their homework. Present Simple

On the internet you are anonymous and you don't know who you are talking to in the chat rooms. Present simple

I'm a great believer in the Internet. Present Cont.

In fact, the Internet has been successfully used by people to find
>lifelong partners. Past Perfect

Nie. Porownaj z Twoim nastepnym zdaniem.

>I'm a great believer in the Internet. Present Cont.

Nie. Porownaj ze swoim poprzednim zdaniem.

>In fact, the Internet has been successfully used by people to find
lifelong partners.
a to jest Present Perfect ?


>I'm a great believer in the Internet.
Czyli to jest Present Simple

Dzięki za odpowiedzi ;)