At times, worrying is a normal, ________ response to a difficult event or situation – a loved one being injured in an accident, for example.

The thief must have hidden somewhere in the _______ area．

---Do you know what makes her so _______? ---Too many useless text messages she has received.

The increase of the number of the students makes the limited computers not ________ to each student.

The passer-by jumped into the cold water to save the _____ boy, who cried for help, but it was too late and the boy was _______ at last.