Improve knowledge base

1 files changed, 2 insertions, 2 deletions

diff --git a/source/know/concept/time-dependent-perturbation-theory/index.md b/source/know/concept/time-dependent-perturbation-theory/index.md
index b4b35e1..841c219 100644
--- a/source/know/concept/time-dependent-perturbation-theory/index.md
+++ b/source/know/concept/time-dependent-perturbation-theory/index.md
@@ -70,11 +70,11 @@ $$\begin{aligned}
 \end{aligned}$$
 
 And so forth. The pattern here is clear: we can calculate the $$(j\!+\!1)$$th
-correction using only our previous result for the $$j$$th correction.
+correction using our result for the $$j$$th correction.
 The only purpose of $$\lambda$$ was to help us collect its orders;
 in the end we simply set $$\lambda = 1$$ or absorb it into $$\hat{H}_1$$.
 Now we have the essence of time-dependent perturbation theory,
-we cannot go any further without considering a specific $$\hat{H}_1$$.
+and we cannot go any further without considering a specific $$\hat{H}_1$$.