Sometimes, ________ we show our gratitude for a person is reflected in the kind of food we serve him or her.
A．when B．whether
C．why D．how
It remains to be seen ________ this plan is practical enough to keep the project going.
A．whether B．how
C．where D．when
Helen has got ________ it takes to be a great tennis player. In other words, she has the potential to become world famous.
A．how B．what
C．when D．that
Israel was created as a homeland for homeless Jews after World War Ⅱ. However, the creation of Israel in ________ used to be Palestine left many Palestinians homeless.
A．what B．which
C．where D．that
After ________ seemed a hopeless wait, four coalminers trapped in the mine for 125 hours were finally rescued in Heilongjiang Province.
A．when B．that
C．it D．what
In the office an electrical engineer is looking through the instructions to know ________ the heat system works before the repair work.
A．whether B．why
C．how D．that
