Beyond the regular patterns, several common verbs are irregular and need to be learned individually. Tener (to have) is conjugated yo tengo, tú tienes, él/ella/usted tiene, nosotros tenemos, ellos/ustedes tienen. It is also used in many idiomatic expressions where English uses "to be": tener hambre (to be hungry), tener sed (to be thirsty), tener sueño (to be sleepy), tener miedo (to be afraid), and tener razón (to be right). Ir (to go) is conjugated yo voy, tú vas, él/ella/usted va, nosotros vamos, ellos/ustedes van. Ir also combines with a and an infinitive to express the near future, similar to English "going to": Voy a estudiar means "I am going to study," and Vamos a comer means "we are going to eat."
Two more important irregulars are hacer (to do/make) and the stem-changing verbs querer and poder. Hacer conjugates as yo hago, tú haces, él/ella/usted hace, nosotros hacemos, ellos/ustedes hacen; only the yo form (hago) is irregular. Querer (to want/love) and poder (to be able to) change their stems in most forms: quiero, quieres, quiere, queremos, quieren for querer and puedo, puedes, puede, podemos, pueden for poder, with the nosotros form reverting to the regular stem (queremos, podemos). These verbs also open up a wide range of expressions, since Spanish uses hacer for many common weather phrases.
Spanish also distinguishes between two verbs that both mean "to know." Saber refers to knowing facts or learned skills and is conjugated yo sé, tú sabes, él sabe, nosotros sabemos, ellos saben. Conocer refers to being familiar with people, places, or things and is conjugated yo conozco, tú conoces, él conoce, nosotros conocemos, ellos conocen. So Saber español means "to know Spanish" as a skill, while Conocer España means "to know Spain" as a place you have visited.