样 yàng = 木 (mù, wood) + 羊 (yáng, the phonetic). It is a pictophonetic compound: 木 on the left once supplied a meaning tied to wood (the traditional form 樣 originally named a kind of oak and its acorn), while 羊 on the right carries the sound yáng to yàng. The old botanical sense has fallen away, and only the pictophonetic frame survives in the modern character.

What the word came to mean is appearance and kind. A 样 is the look or form of a thing, and from that one idea three senses branch:

1. Shape, appearance, manner. How something looks or presents itself: 样子 yàngzi (appearance, manner), 模样 múyàng (looks, the cast of a face).
2. Kind, type, pattern. One sort among many: 一样 yíyàng (the same kind, alike), 样式 yàngshì (style, pattern), 各种各样 gè zhǒng gè yàng (all kinds).
3. Sample, model. One specimen held up to stand for the rest: 样品 yàngpǐn (a sample), 榜样 bǎngyàng (a role model, a thing to copy).

From these come the busiest 样 words of all, the manner words that point at how something is done: 这样 zhèyàng (this way), 那样 nàyàng (that way), 怎样 zěnyàng (in what way, how). The thread throughout is form and likeness: the look a thing has, the type it belongs to, and the model it is measured against.

Some of the highest-frequency words in spoken Chinese are 样 manner words, built by fixing a pointing word to 样. 这样 zhèyàng is "this way, like this"; 那样 nàyàng is "that way, like that"; 怎样 zěnyàng is "in what way, how." Each names not a thing but a manner, the how of an action or the form of a state: 别这样 "don't be like this," 事情怎样了 "how did things turn out."

怎样 overlaps heavily with 怎么 zěnme. Both ask "how," but 怎样 leans a little more formal and tends to ask after manner or outcome (你怎样 "how are you doing"), while 怎么 is the workaday "how" of method and reason (怎么做 "how to do it," 怎么了 "what is the matter"). In casual speech they are often interchangeable, and 这样 / 那样 likewise pair with the shorter 这么 / 那么 for degree.

The wood radical 木 on the left is a faint memory of the character's origin in a kind of tree, but let it go: what 样 means now is the look and kind of a thing. Picture a single sample on a shelf, held up to show what the whole batch is like. That is 样品, and from it everything else follows.

Ask of any 样 word what aspect of "form" it points at. Two things sharing a form are 一样 (the same). A form worth copying is a 榜样 (role model). The form an action takes is its manner: 这样 (this way), 那样 (that way), 怎样 (which way, how). Whenever you meet 样, you are being shown the shape or kind of something.