cause and effect
opinion
idioms
100

cause havoc

cause damage

100

to be convinced 

to be sure something is right

100

take a back seat

not do anything, let others act

200

cause concern

make somebody worried/alarmed

200

maintain 

insist on believing 

200

to be in a tight corner

to be in a situation that is hard to get out of

300

unforseen outcome

results that couldn't be predicted

300

reckon

verb for opinion about something that is likely to happen

300

get to the bottom of things

find the true explanation for the state of things

400

sparkle off riots

cause demonstrations

400

doubt

not be sure about something

400

to get a grasp of something

understand/find out

500

immediate cause

direct cause

500

suspect

have a strong feeling about something

500

to sweep something under the carpet

ignore things, forget things without solving them