I can crawl you can crawl she can crawl we can crawl you can crawl they can crawl
V-ing form
I can be crawling you can be crawling she can be crawling we can be crawling you can be crawling they can be crawling
Perfect
I can have crawled you can have crawled she can have crawled we can have crawled you can have crawled they can have crawled
V-ing perfect
I can have been crawling you can have been crawling she can have been crawling we can have been crawling you can have been crawling they can have been crawling
Negation
Simple form
I can't crawl you can't crawl she can't crawl we can't crawl you can't crawl they can't crawl
V-ing form
I can't be crawling you can't be crawling she can't be crawling we can't be crawling you can't be crawling they can't be crawling
Perfect
I can't have crawled you can't have crawled she can't have crawled we can't have crawled you can't have crawled they can't have crawled
V-ing perfect
I can't have been crawling you can't have been crawling she can't have been crawling we can't have been crawling you can't have been crawling they can't have been crawling
Interrogative form
Simple form
can I crawl? can you crawl? can she crawl? can we crawl? can you crawl? can they crawl?
V-ing form
can I be crawling? can you be crawling? can she be crawling? can we be crawling? can you be crawling? can they be crawling?
Perfect
can I have crawled? can you have crawled? can she have crawled? can we have crawled? can you have crawled? can they have crawled?
V-ing perfect
can I have been crawling? can you have been crawling? can she have been crawling? can we have been crawling? can you have been crawling? can they have been crawling?
Interro-negative form
Simple form
can't I crawl? can't you crawl? can't she crawl? can't we crawl? can't you crawl? can't they crawl?
V-ing form
can't I be crawling? can't you be crawling? can't she be crawling? can't we be crawling? can't you be crawling? can't they be crawling?
Perfect
can't I have crawled? can't you have crawled? can't she have crawled? can't we have crawled? can't you have crawled? can't they have crawled?
V-ing perfect
can't I have been crawling? can't you have been crawling? can't she have been crawling? can't we have been crawling? can't you have been crawling? can't they have been crawling?