1 surely

2 certainly

3 necessarily

4 fixed

5 a certain (extent etc)

6 given

7 particular

8 must

1 to be connected

2 traffic

3 transportation

4 communications

5 liaison

1 to set

2 to fix

3 to determine

4 to decide

5 to order

1 to fix

2 to settle

3 to wangle

1 common

2 ordinary

3 general

4 average

1 lit. doesn't (even) enter a single aperture (of one's head)

2 I don't understand a word (idiom)

3 it's all Greek to me

1 (idiom) it's a deal

2 that's settled then

1 grasp this fundamental point and all the rest will follow (idiom)

1 to act in collusion (idiom)

1 mutual exchange of assistance (idiom)

2 to benefit from each other's strengths and make up each other's shortfalls

3 to reciprocate with material assistance

4 scratch each other's back