Exercise 67:

"for" tells you how long a period of time is. "since" tells you when the period of time started.

Maria has lived in England SINCE 1988 (tells you when the period started).

She has been married to James FOR four years (how long the period of time is).

Exercise 68:

This one is more complicated. Verb tenses require a lot of nuanced explanation. The answer for #2 for example, could actually be any of the three verb tenses mentioned in the question:

"Our team goes to France next week." (Simple Present: a statement of fact. Possible, but not the best answer here.)

"Our team is going to France next week." (Present Continuous can be used to talk about future travel plans)

"Our team is going to go to France next week." (Simple Future with "be going to" for future actions at a definite time.)

Like Jerome, I'm going to let you do the rest of these ones :)

Exercise 69:

This link will help you understand:

https://learnenglish.britishcouncil.org/en/quick-grammar/just-yet-still-already

Help!)

2) for

3) since

4) for

5) since

Now you try the rest :)