The structure of #3 suggests this bird is a Eurasian Collared Dove. It body seems fairly bulky and the tail is relatively long (RTD is very short-tailed)
The easiest way to separate these is by size (RTD is tiny) but this is hard to judge on the photo, although the bird seems too large for RTD. Other useful features are the pure white underwing and grey upperwing 'triangle' of ECD and the tail pattern.
Date is also a useful clue - RTD is commoner on passage (rarer in winter) but ECD is a localised resident, with a pair often seen near the car park at Mai Po.
I agree with Yellow Wagtail and Daurian Redstart for the other birds.
