Certain nouns in the English language should be considered male or female. Here are some and why...

-SWISS ARMY KNIFE-
Male, because even though it appears useful for a wide variety of work, it spends most of its time just opening bottles.

-KIDNEYS-
Female, because they always go to the bathroom in pairs.

-TIRE-
Male, because it goes bald and often is over inflated.

-HOT AIR BALLOON-
Male, because to get it to go anywhere you have to light a fire under it... and, of course, there's the hot air part.

-SPONGES-
Female, because they are soft and squeezable and retain water.

-WEB PAGE-
Female, because it is always getting hit on.

-SHOE-
Male, because it is usually unpolished, with its tongue hanging out.

-COPIER-
Female, because once turned off, it takes a while to warm up. Because it is an effective reproductive device when the right buttons are pushed. Because it can wreak havoc when the wrong buttons are pushed.

-ZIPLOC BAGS-
Male, because they hold everything in, but you can always see right through them.

-SUBWAY-
Male, because it uses the same old lines to pick people up.

-HOURGLASS-
Female, because over time, the weight shifts to the bottom.

-HAMMER-
Male, because it hasn't evolved much over the last 5,000 years, but it's handy to have around.

-REMOTE CONTROL-
Female...Ha! You thought I'd say male. But consider, it gives man pleasure, he'd be lost without it, and while he doesn't always know the right buttons to push, he keeps trying.