Rewrite the following sentences by adding words from the parentheses. replace the modal verb can (could) with the expression to be able to if necessary. 1. i can give you my book for a couple of days (after i have read it). 2. he can ski (for ten years). 3. we knew that she could swim (since a child). 4. you cannot take part in this serious sport competition (until you have mastered good skills).
2. He has been able to ski for ten years
3. we knew that she was able to swim when she was a child
4.You are not able to take part in this serious competition until you have mastered good skills