Line
Attentive observation and a developed vocabulary will enable you to evaluate the formal elements of an artwork. One of the key elements of form is line. There are many types of lines—straight, curved, zigzag, spiral, expressive, and so on. In Women Ironing by Jacob Lawrence, we can find several examples of line, all of which are very hard and expressive.
Line can also be used to create the sense of depth. This technique is known as linear perspective.