1.
Scoring: MP
Pass-(1♦)-2♣-(2♠)-X-(4♠)-Pass-Pass-?
Do you like X? What now?
2.
Scoring: MP
(Pass)-1♠-(2♦)-3♦-(Pass)-3♠-(Pass)-?
3.
Scoring: MP
2S-(Pass)-?
Your partner will virtually always have 6 spades here. 2S is just a 6-10 weak two.
4. And lastly, bid these hands to 6NT by South, after the start 1♠-2♥ (GF).
Scoring: MP