had to, could or couldn't?

Slaves ... live freely.

• could

• couldn't

• had to

Slaves ... work long hours.

• could

• couldn't

• had to

Slaves ... read or write.

• could

• couldn't

• had to

Slaves ... sing while working in the fields.

• could

• couldn't

• had to

Slaves ... run away to escape their masters.

• could

• couldn't

• had to

Slaves ... use the Underground Rairoad to escape.

• could

• couldn't

• had to

Runaway slaves ... disguise themselves not to be recognized.

• could

• couldn't

• had to

Runaway slaves ... follow the North Star.

• could

• couldn't

• had to

Runaway slaves ... speak to anyone.

• could

• couldn't

• had to

When they arrived north, slaves ... be free!

• could

• couldn't

• had to