I can cling you can cling he can cling we can cling you can cling they can cling
V-ing form
I can be clinging you can be clinging he can be clinging we can be clinging you can be clinging they can be clinging
Perfect
I can have clung you can have clung he can have clung we can have clung you can have clung they can have clung
V-ing perfect
I can have been clinging you can have been clinging he can have been clinging we can have been clinging you can have been clinging they can have been clinging
Negation
Simple form
I cannot cling you cannot cling he cannot cling we cannot cling you cannot cling they cannot cling
V-ing form
I cannot be clinging you cannot be clinging he cannot be clinging we cannot be clinging you cannot be clinging they cannot be clinging
Perfect
I cannot have clung you cannot have clung he cannot have clung we cannot have clung you cannot have clung they cannot have clung
V-ing perfect
I cannot have been clinging you cannot have been clinging he cannot have been clinging we cannot have been clinging you cannot have been clinging they cannot have been clinging
Interrogative form
Simple form
can I cling? can you cling? can he cling? can we cling? can you cling? can they cling?
V-ing form
can I be clinging? can you be clinging? can he be clinging? can we be clinging? can you be clinging? can they be clinging?
Perfect
can I have clung? can you have clung? can he have clung? can we have clung? can you have clung? can they have clung?
V-ing perfect
can I have been clinging? can you have been clinging? can he have been clinging? can we have been clinging? can you have been clinging? can they have been clinging?
Interro-negative form
Simple form
can I not cling? can you not cling? can he not cling? can we not cling? can you not cling? can they not cling?
V-ing form
can I not be clinging? can you not be clinging? can he not be clinging? can we not be clinging? can you not be clinging? can they not be clinging?
Perfect
can I not have clung? can you not have clung? can he not have clung? can we not have clung? can you not have clung? can they not have clung?
V-ing perfect
can I not have been clinging? can you not have been clinging? can he not have been clinging? can we not have been clinging? can you not have been clinging? can they not have been clinging?