An important assignment / task carried out by someone
Mission
To watch something or someone to see how they behave / To study something
Make observations
Do experiments
Conduct experiments
Things which don't often happen
Rare occassions
Not easy to use, do, or understand.
Complicated
Switching on
Powering on
Come into sight / Become visible
Appeared
Asked
Requested
The radio wave sent / received by something
Signal
A closet where clothes are kept
Wardrobe
The necessary items for a particular purpose
Equipment
Utensils used for eating
Cutlery
