close to，go off，pay attention，get lost，set off，be careful of

（1）

Pay attention

Pay attention

，please．You have to follow me．
（2）Hiking is a great way to travel．You will get

closed to

closed to

nature and take exercise．
（3）We will have to

set off

set off

early to avoid the heavy traffic tomorrow morning．
（4）

Be careful of

Be careful of

the falling stones when you are going rock climbing．
（5）The litter girl

got lost

got lost

in the dark forest．She began to cry．
（6）The guide told us not to

go off

go off

on our own during the travel．