a) 1 ; 11 

b) 1 ; 12 

c) 3 ; 4 ; 7 

d) 6 

e) 10 

f) 9 

g) 5 ; 8

1 Present (The past form of can't is couldn't)

2 Past (The present form of ought to is ought to)

3 Present (The past form of need is needed)

4 Past (The present