how to iphone some typing

Type "welll" (3 L's) and the iPhone will auto correct to "We'll"

Type "Helll" (3 L's) and the iPhone will auto correct to "He'll"

Type "itsa" and the iPhone will auto correct to "It's"

Type "weree" (2 E's) and the iPhone will auto correct to "We're"

(In general, repeating the last letter will tell us its a contraction. The "itsa" is an exception since it could go either way. Think "it's a..."

No need for jumping over to the secondary keyboard at all for the apostrophe.