1.My parents____(to buy) a new microwave a week ago.
2.Dan ____(not to thank ) me for my help.
3.Martha ____(to know) his address.
4.He ____(to teach) me to swim last summer.
5.My sister____(not to help) me to tidy our room last Saturday.
6.She _____(to make) you some sandwiches and a cup of tea for breakfast.