Co
Mid
De
Re
Pre
100

Copilots 

Two pilots who work together

100

Midmorning 

In the middle of the morning

100

Dehydrate 

To remove water

100

Reheat 

To heat up again 

100
Pretest

An assignment given before a test 

200

Co-captains 

Two team captains working together

200

Midday

In the middle of the day

200

Decode

To solve (take away) a code from a coded message

200

Redo

To do something again 

200

Preschool

School before elementary school 
300
Coexist 

Existing together 

300

Midair 

In the middle of the air

300

Declutter 

To remove unnecessary items from an area

300

Rearrange

To change the position of something; to arrange something again
300

Prepaid 

paid for in advance

400

Cooperate 

To work together 

400
Midfield 

In the middle of the field 

400

Deflate

To remove the air 

400

Refill

To fill something again 

400

Preview 

To see something before it is presented to the public 
500

Committee 

A group of people working together 

500

Midway 

Toward the middle of something 

500

Demote 

To give someone a lower job position 

500

Refresh

To give something new life/energy; To update the display on a computer screen 

500

Prefix 

Letters/part of a word added before a root word