New Zealand _____________the Maori tribe.
________ it rain tomorrow, we should have to put off the visit to the Yangpu Bridge.
If we had taken such effective measures much earlier, the river ________ so seriously now.
George is going to talk about the geography of his country, but I'd rather he ________ more on its culture.
Don't handle the vase as if it ________ made of steel.
Jack is a great talker. It's high time that he ________ something instead of just talking.