Difference 【Difference】between は (wa) and が (ga) which are subject marking particles
Use が if you want to make the subject of a sentence specific and exclusive. Other than that, use は.
Grammar
Difference 
Sentence pattern look, sound, seem + adjective:【adj. stem form + そうです】
On this page, you can learn Japanese grammar for 'look, sound or seem + adjective'.
Sentence pattern be going (or about) to :【verb stem form + そうです】
On this page, you can learn Japanese grammar for 'be going (or about) to'.
Sentence pattern 【Japanese grammar: According to A】: A によると
A によると is convenient when you need to refer to resources to support your opinion. Let's see some examples.
Sentence pattern 【Japanese grammar: conjunction】ので（node）= because: how to express reason
Let's learn how to say those sentences in Japanese: I like John because he is handsome. I like a phone because it is convenient. I don't like tomatoes because it is not yummy. My older sister works because she wants money.
Sentence pattern Many people think:【と思う人は多いです。】
On this page, you can learn Japanese grammar to talk about what many people think.
Sentence pattern Verb + like A:【A のように Verb】
On this page, you can learn Japanese grammar for 'Verb + like + Noun'.
Sentence pattern Noun + like A:【A のような Noun】
On this page, you can learn Japanese grammar for 'Noun + like A'.
Sentence pattern 【Japanese grammar】verb て form + います (imasu) = be + verb-ing: Present Continuous
Let's learn how to say those sentences in Japanese: My mother is eating pasta with my older sister. I am playing with friends in a park. My father is listening to music in a living room now. My older brother is drinking sake with friends now. My uncle is playing baseball at a stadium now.
Sentence pattern from A to B:【A から B まで】
On this page, you can learn Japanese grammar, 'from A to B'.