1. yesterday, i got lost at the crowded market and ..... find my mother.
b. could not
d. can not
2. i ...... swim well. but yesterday, i got a severe cramp on my legs, so i .... finish my practice.
a. can- could
b. could - can't
c. can't - could not
d. can - could not
3. M : can i have a seat on row 5?
U: I am sorry the seat s have been all reseved you .... have one on row 6.
M: Okay. thank you.
b. am able to