Where

where → ウェー,ウェ
where/we're/wear → ウェー(同じ発音)
カタカナで表記すると変化をつけるのは何故？？

there/they're/their → thエー(同じ発音)

did you

did you → ディジュ

同化
D + Y = J

(Where)'d you → ジュ
Where did you → ウェジュ

get them

get (th)em → ゲデム
give (h)im → ギヴィム
give (h)er → ギヴァ
give (th)em → ギヴェム
meet (h)im → ミーディム
meet (h)er → ミーダ
meet (th)em → ミーデム

置き換え

Where did you go?
Where did you buy it?
Where did you go meet him?

What did you → ワジュ

What did you do?
What did you say?
What did you buy?

Where did you take them? → ウェジュテイケム
What did you tell them? → ワジュテレム