[Kasomi]

Okay, I noticed you deleted the second sentence, but I wanted to help, too, if I could.

For the differences between "wa" and "ga", normally the first is a topic marker, and the second is the subject (normally doing something) that precise the subject.

Example:

Kono hana wa tane ga haeteiru.

The seed (of this flower) is growing. or About this flower, the seed is growing. (this seems very unnatural, but it could be a translation to make the difference)

What is in the parentheses is what the topic marker here adds. Without it, the sentence is vague. It could be any flower's seed.

Tane ga haeteiru. The seed is growing. or The seeds are growing. or A seed is growing (Depends on context given)

See?

(Hope I didn't make any mistake, did I?)