diff --git a/.travis.yml b/.travis.yml
index 455f3c0..45c29f6 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,6 @@
 language: clojure
-lein: lein2
-script: lein2 midje :config .midje-grading-config.clj
+lein: lein
+script: lein midje :config .midje-grading-config.clj
 jdk:
   - openjdk7
 notifications:
diff --git a/src/predicates.clj b/src/predicates.clj
index 158b1ea..b66374f 100644
--- a/src/predicates.clj
+++ b/src/predicates.clj
@@ -1,41 +1,45 @@
 (ns predicates)
 
 (defn sum-f [f g x]
-  :-)
+  (+ (f x) (g x)))
 
 (defn less-than [n]
-  :-)
+  (fn [x] (< x n)))
 
 (defn equal-to [n]
-  :-)
+  (fn [x] (== x n)))
 
 (defn set->predicate [a-set]
-  :-)
+  (fn [x] (contains? a-set x)))
 
 (defn pred-and [pred1 pred2]
-  :-)
+  (fn [x] (and (pred1 x) (pred2 x))))
 
 (defn pred-or [pred1 pred2]
-  :-)
+  (fn [x] (or (pred1 x) (pred2 x))))
 
 (defn whitespace? [character]
   (Character/isWhitespace character))
 
 (defn blank? [string]
-  :-)
+  (every? whitespace? string))
 
 (defn has-award? [book award]
-  :-)
+  (contains? (:awards book) award))
 
 (defn HAS-ALL-THE-AWARDS? [book awards]
-  :-)
+  (let [book-has-award? (fn [award] (has-award? book award))]
+    (every? book-has-award? awards)))
 
 (defn my-some [pred a-seq]
-  :-)
+  (first (filter identity (map pred a-seq))))
 
 (defn my-every? [pred a-seq]
-  :-)
+  (=
+    (count a-seq)
+    (count (filter true? (map pred a-seq)))))
 
 (defn prime? [n]
-  :-)
+  (let [n-divides? (fn [divisor] (zero? (mod n divisor)))]
+    (nil? (some n-divides? (range 2 n)))))
 ;^^