The one rule that typically applies to English is that there is always an exception to the rule.  This leads to the question that most of my clients ask:  How can I tell how to pronounce a word with all of these exceptions?  Good news!  There are a few patterns that do better in identifying word pronunciation than others.

86% of the time, in a VC (Vowel-Consonant) pattern, the vowel is pronounced as short:  AT, BAT, BET, MOP, HUT

89% of the time, in a VCC (Vowel-Consonant-Consonant) pattern, the vowel is pronounced as short:  BAND, BEST, LICK, LOCK, LUCK

81% of the time, in a VCE (Vowel-Consonant-silent E) pattern, the vowel is pronounced as long:  ATE, TAKE, PETE, MOPE, TUBE

77% of the time, in a VVC (Vowel-Vowel-Consonant) pattern, the vowel is pronounced as long:  SAIL,HEAT, ROAD

77% of the time, in a CV (Consonant-Vowel) pattern, the vowel is pronounced as long: HE, HI, GO, CRY