好几 + Measure Word + Noun
好几 (hǎojǐ) means "quite a few" or "several" and emphasizes that the number is more than just a couple. It is placed before a measure word and noun, as in 好几个小时 (quite a few hours). Compared to 几, which is neutral, 好几 stresses that the quantity is notably large.
我们等了好几个小时才买到票。
Wǒmen děngle hǎo jǐ gè xiǎoshí cái mǎi dào piào.
We waited for several hours before we could buy tickets.
他去过好几个国家,见识很广。
Tā qùguò hǎo jǐ gè guójiā, jiànshi hěn guǎng.
He has been to quite a few countries and is very well-informed.
这道数学题我做了好几遍才做对。
Zhè dào shùxué tí wǒ zuòle hǎo jǐ biàn cái zuò duì.
I worked on this math problem several times before getting it right.