Grammar fix in Chapter 8 (#835)

Grammatical mistake in paragraph 278, change "to active" to "to be activated".

08_routing_htlcs.asciidoc

@@ -275,7 +275,7 @@ Bitcoin Script is flexible enough that there are dozens of ways to implement a f
 
 The fairness protocol for routing used in the Lightning Network today is called a Hash Time-Locked Contract (HTLC). HTLCs use a hash pre-image as the secret that unlocks a payment, as we saw in the gold coin example in this chapter. The recipient of a payment generates a random secret number and calculates its hash. The hash becomes the condition of payment and once the secret is revealed, all the participants can redeem their incoming payments. HTLCs offer atomicity, trustless operation and multihop security. While HTLCs are efficient and very simple, they involve a small compromise of privacy (see <<htlc_privacy_compromise>>).
 
-Another proposed mechanism for implementing routing is a _Point Time-Locked Contract (PTLC)_. PTLCs also achieve atomicity, trustless operation and multihop security, but do so with increased efficiency and better privacy.  Efficient implementation of PTLCs depends on a new digital signature algorithm called _Schnorr signatures_, which is expected to active in Bitcoin in 2021.
+Another proposed mechanism for implementing routing is a _Point Time-Locked Contract (PTLC)_. PTLCs also achieve atomicity, trustless operation and multihop security, but do so with increased efficiency and better privacy.  Efficient implementation of PTLCs depends on a new digital signature algorithm called _Schnorr signatures_, which is expected to be activated in Bitcoin in 2021.
 
 === Revisiting our example