diff --git a/cmdutils.h b/cmdutils.h
index 78867b78a1..1dfe68e365 100644
--- a/cmdutils.h
+++ b/cmdutils.h
@@ -204,8 +204,8 @@ void show_protocols(void);
 void show_pix_fmts(void);
 
 /**
- * Return a positive value if reads from standard input a line
- * starting with [yY], otherwise returns 0.
+ * Return a positive value if a line read from standard input
+ * starts with [yY], otherwise return 0.
  */
 int read_yesno(void);
 
diff --git a/libavcodec/alsdec.c b/libavcodec/alsdec.c
index 6040ce34b6..7bf574a9f6 100644
--- a/libavcodec/alsdec.c
+++ b/libavcodec/alsdec.c
@@ -454,7 +454,7 @@ static void parse_bs_info(const uint32_t bs_info, unsigned int n,
 }
 
 
-/** Read and decodes a Rice codeword.
+/** Read and decode a Rice codeword.
  */
 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
 {
@@ -490,8 +490,8 @@ static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
 }
 
 
-/** Read block switching field if necessary and sets actual block sizes.
- *  Also assures that the block sizes of the last frame correspond to the
+/** Read block switching field if necessary and set actual block sizes.
+ *  Also assure that the block sizes of the last frame correspond to the
  *  actual number of samples.
  */
 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
@@ -980,7 +980,7 @@ static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
 }
 
 
-/** Read and decodes block data successively.
+/** Read and decode block data successively.
  */
 static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
 {
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 5841d6a4c8..8727c60842 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -48,7 +48,7 @@
 #define AV_TIME_BASE_Q          (AVRational){1, AV_TIME_BASE}
 
 /**
- * Identifie the syntax and semantics of the bitstream.
+ * Identify the syntax and semantics of the bitstream.
  * The principle is roughly:
  * Two decoders with the same ID can decode the same streams.
  * Two encoders with the same ID can encode compatible streams.
@@ -3533,7 +3533,7 @@ attribute_deprecated int avcodec_decode_subtitle(AVCodecContext *avctx, AVSubtit
 
 /**
  * Decode a subtitle message.
- * Return a negative value on error, otherwise returns the number of bytes used.
+ * Return a negative value on error, otherwise return the number of bytes used.
  * If no subtitle could be decompressed, got_sub_ptr is zero.
  * Otherwise, the subtitle is stored in *sub.
  *
diff --git a/libavcodec/qcelpdec.c b/libavcodec/qcelpdec.c
index 4394ec472d..0441e1fcae 100644
--- a/libavcodec/qcelpdec.c
+++ b/libavcodec/qcelpdec.c
@@ -594,7 +594,7 @@ static void lspf2lpc(const float *lspf, float *lpc)
 }
 
 /**
- * Interpolate LSP frequencies and computes LPC coefficients
+ * Interpolate LSP frequencies and compute LPC coefficients
  * for a given bitrate & pitch subframe.
  *
  * TIA/EIA/IS-733 2.4.3.3.4, 2.4.8.7.2