3. Is Ann cutting the grass?
Yes, she is.
4. Are the children knitting?
No, they aren't.
5. Are dogs chasing a cat?
Yes, they are.
6. Is postman delivering letters?
Yes, he is.
7. Is grandmother standing by the gate?
No she isn't.
-s
opens, puts, buys, likes, sits, plays, says, begins
-es
fixes, kisses, washes, teaches, passes, cathes