1) This poem uses expressive techniques and metaphorical rhetorical techniques to express the author's subjective feelings. It is written gorgeously and delicately, setting the rhythm and rhyme for the poem.
2) Not exactly equal. For example, "Night Rain Sends to the North" is a combination of expression technique and subject matter, both of which are to support objects and express aspirations. However, this poem "Ode to Butterflies" does not mean that its subject matter is: lyrical.