Colour/B&W pairs

As I've said, I'm working more on my technical skills; with this post, trying to focus on using greyscale value and not just colour, even when photographing something as colourful as Dutch flowers. Here are some pictures of the same things, taken in both colour and B&W. As with the previous pictures, these were all shot in the form in which they appear, either colour or greyscale, so you'll notice slight differences between them.