Mr. White is a careful and experienced engineer, so he is often        to finish some challenging tasks.

(2013·北京东城区高三期末)I asked for some more cake，but there was ________ left.

I think this software is of little use to your work. It is really a ________ of money. 

We are at your service. Don’t ________ to turn to us if you have any further problems.

---Why do you look so happy?---My aunt has bought a new car and she will invite me to go for a _____ this weekend.