diff --git a/10/index.html b/10/index.html
index e4deee4..3adaac2 100644
--- a/10/index.html
+++ b/10/index.html
@@ -44,12 +44,11 @@
     <div class="box box-top">
       <p>
         a is an emotion particle! you can put it after a word or a sentence to
-        intensify or emphasize what came before it
+        intensify or emphasize what came before it.
       </p>
       <p>
         put on its own it means something like <i>ah</i>, <i>oh!</i>, or some
-        other emotion sound, and more than three a's in a row often means
-        laughter.
+        other emotion sound, and several a's in a row often means laughter.
       </p>
     </div>
 
diff --git a/11/index.html b/11/index.html
index 09a78ce..5e04225 100644
--- a/11/index.html
+++ b/11/index.html
@@ -46,7 +46,7 @@
       <p>jo is not the same as english's general to have.</p>
       <div class="quote">
         <p class="sentence">i <span class="preverb">have to</span> work</p>
-        <p>~ mi pali</p>
+        <p>~ mi wile pali</p>
       </div>
       <div class="quote">
         <p class="sentence">
diff --git a/18/index.html b/18/index.html
index dbd30b2..eee3559 100644
--- a/18/index.html
+++ b/18/index.html
@@ -43,8 +43,7 @@
         meaning <i>nothing, one, two, many, everything</i>.
       </p>
       <p>
-        toki pona doesn't have any more specific amounts than this, because
-        numbers are rarely necessary to communicate anything.
+        other number systems exist, but this one will usually be all you need.
       </p>
       <p>
         often numbers instead end up obscuring what a quantity really means,
diff --git a/19/index.html b/19/index.html
index e9a0f5c..a5940de 100644
--- a/19/index.html
+++ b/19/index.html
@@ -125,10 +125,6 @@
         <summary>what's the meaning of this word?</summary>
         <p>kon pi nimi ni li seme</p>
       </details>
-      <details>
-        <summary>hey, give me that tasty fruit over there</summary>
-        <p>o pana e kili pona lon ni tawa mi</p>
-      </details>
       <details>
         <summary>hold on. is this almost the end of the course?</summary>
         <p>o awen · pini pi lipu sona ni li kama anu seme</p>
diff --git a/5/index.html b/5/index.html
index c3923fe..c447657 100644
--- a/5/index.html
+++ b/5/index.html
@@ -32,8 +32,8 @@
     <h3 class="title box-title sub-title">~ preverbs</h3>
     <div class="box box-top">
       <p>
-        󱤖 kama - arriving, coming, future, summoned; (pv.) to become, manage,
-        to, succeed in
+        󱤖 kama - arriving, coming, future, summoned; (pv.) to become, manage to,
+        succeed in
       </p>
       <p>
         󱥷 wile - must, need, require, should, want, wish; (pv.) to want to, to
@@ -70,6 +70,7 @@
     <div class="box box-top">
       <p>preverbs go before the predicate and modify it.</p>
       <p>preverbs can only be modified with the word ala, to negate it.</p>
+      <p>preverbs can be stacked.</p>
       <div class="quote">
         <p>
           <span class="subject">subject</span> li
@@ -115,6 +116,7 @@
 
       <details>
         <summary>jan li kama sona toki pona</summary>
+        <p>people come to know how to speak well</p>
         <p>people learn to speak toki pona</p>
       </details>
 
@@ -181,6 +183,15 @@
         <summary>i wanna learn toki pona</summary>
         <p>mi wile kama sona (e) toki pona</p>
       </details>
+      <details class="hint">
+        <summary>note</summary>
+        <p>
+          (there is a slight difference in meaning depending on whether you use
+          e or not!)
+        </p>
+        <p>without e: "i want to come to know how to speak well"</p>
+        <p>with e: "i want to come to know a good language"</p>
+      </details>
 
       <details>
         <summary>i can't see that</summary>
diff --git a/7/index.html b/7/index.html
index c4fc353..c0d0d56 100644
--- a/7/index.html
+++ b/7/index.html
@@ -198,7 +198,7 @@
 
       <details>
         <summary>people work for bad reasons</summary>
-        <p>ijo li pali tan tan ike</p>
+        <p>ijo li pali tan ike</p>
       </details>
 
       <details>
diff --git a/9/index.html b/9/index.html
index 02acae1..466f5e2 100644
--- a/9/index.html
+++ b/9/index.html
@@ -109,6 +109,12 @@
         to a jan!
       </p>
     </div>
+    <div class="box box-top">
+      <p>
+        in practice, many people do use <i>jan</i> for someone/anyone/everyone
+        etc.
+      </p>
+    </div>
 
     <h3 class="title box-title sub-title">~ examples</h3>
     <div class="box">
diff --git a/extra.html b/extra.html
index 7cc8b57..0336899 100644
--- a/extra.html
+++ b/extra.html
@@ -73,7 +73,7 @@
       </p>
       <p>
         󱦠 pake - stop, cease, halt; to block the way, to interrupt; to prevent
-        (<i>pini</i>
+        (<i>pini</i>)
       </p>
       <p>
         󱦡 apeja - guilt, shame, shun, stigma, disgrace; to accuse, to single