надо вставить do/does, или don't/doesn't... ...your mother ski?-yes, she... ...Tom and Bob ski?-yes, they... ...you help mother?-yes, i... ...Tom help mother?-no, he... ...his aunt swim?-no, she... ...his aunts skate?-no, they... ...Tom and you see the bird?-no, we... ...they swim?-yes, they... ...you ski?-no, we... ...this bird sing?-yes, it... ...that dog jump?-no, it...