Activated abilities contain a colon. They're generally written "[Cost]: [Effect]." Some keyword abilities (such as equip) are activated abilities and will have colons in their reminder text. An activated mana ability is one that produces mana as it resolves, not one that costs mana to activate.

If the ability is modal (that is, if it says, "Choose one —" or similar), the mode is copied and can't be changed.

Any choices made when the ability resolves won't have been made yet when it's copied. Any such choices will be made separately when the copy resolves. If a triggered ability asks you to pay a cost, you pay that cost for the copy separately.

The source of the copy is the same as the source of the original ability.

You can't choose to pay any activation costs for the copy. However, effects based on those costs that were paid for the original ability are copied as though those same costs were paid for the copy.

Peter Parker's Camera's ability targets an ability that is on the stack and creates another instance of that ability on the stack. It doesn't cause any object to gain an ability.

If the ability divides damage or distributes counters among a number of targets, the division and number of targets can't be changed. If you choose new targets, you must choose the same number of targets.

In some cases involving linked abilities, an ability requires information about "the exiled card." When this happens, the ability gets multiple answers. If these answers are being used to determine the value of a variable, the sum is used. If an ability attempts to create a token that is a copy of "the exiled card," it creates a token for each card exiled this way that is a copy of that exiled card.

Triggered abilities use the words "when," "whenever," or "at." They're often written as "[Trigger condition], [effect]." Some keyword abilities (such as prowess) are triggered abilities and will have "when," "whenever," or "at the beginning of" in their reminder text.

If the ability that's copied has an X whose value was determined as it was activated, the copy will have the same value of X.

If an ability is linked to a second ability, copies of that ability are also linked to that second ability. If the second ability refers to "the exiled card," it refers to all cards exiled by the ability and the copy. For example, if The Spot, Living Portal's enters-the-battlefield ability is copied and four cards are exiled, they all return when The Spot, Living Portal dies.