Fill in the blanks:
Doctors use ............. to listen the internal sounds of the body.

Fill in the blank with suitable word. Iron is ...... useful metal.

Fill in the blanks with 'all' or 'whole': His ...... body was covered.

Fill in the blanks: 1. The mechanism used by most mammals to regulate their body temperature are similar to the ones that ..a..use. 2. Human maintain a constant body temperature of ..b.. 3. In summer body temperature is maintained by ..c.. 4. ..d..do not have any mechanism to maintain internal temperatures.